1. Field of the Invention
The present invention generally relates to the field of electronic flight instrument systems (xe2x80x9cEFISxe2x80x9d) and, in particular, moving map displays and primary flight displays presented on electronic screens in aircraft cockpits.
2. Description of the Prior Art
It is well known in the art to provide a display presented on an electronic screen in an aircraft cockpit (known in the art as a xe2x80x9cglass cockpitxe2x80x9d). Most modern commercial and military aircraft have several electronic screens capable of presenting primary flight displays, moving maps or horizontal situation displays, engine parameter displays, and other displays. The present invention is directed to improvements and novel concepts related to the depiction of glide range on moving map displays and primary flight displays presented on electronic screens.
It is known to generate a moving map using navigational symbols whose parameters are stored in electronic memory. It is also known to integrate other types of data onto such moving maps to relay information to the pilot from a vertical perspective. Thus, in some embodiments prior art moving maps offer the capability of integrating lightning strike information, traffic information, radar information, data-link weather and traffic information, geographic information, and bit-mapped graphical chart information with the aforementioned navigational symbol database. However, presentation of aircraft glide range on moving maps is not known in the current state of the art.
The primary flight display of the prior art consists of an electronic presentation of conventional flight data on a single screen. In other words, the symbology and information that would have been presented on separate airspeed indicators, altimeters, vertical speed indicators, artificial horizon/flight directors, and, in some cases, directional indicator/horizontal situation indicators, in pre-glass cockpit aircraft are presented together on a single display known as a primary flight display. Examples of such prior art primary flight displays can be seen in U.S. Pat. Nos. 4,860,007, 5,136,301, 5,359,890, 5,412,382, 5,844,504, and 5,978,715. It is also known to present a perspective background on primary flight displays. An example is shown in U.S. Pat. No. 5,420,582. However, as with moving map depictions, perspective presentation of aircraft glide range on a primary flight display is not known.
The glide range of an aircraft is a critical parameter for single engine aircraft or multi-engine aircraft that are unable to maintain level flight after an engine failure. During the first moments after an engine failure, the pilot is tasked with immediately achieving an optimal glide speed and selecting a flight path to a safe touchdown point. The selection of an emergency flight path is complicated by the effects of wind and terrain. Thus, a pilot aid for achieving the best emergency flight path is needed. These needs are met by the present invention.
The present invention is directed to novel methods for depicting glide range on moving map displays and on perspective-view primary flight displays. These methods involve processing data gathered from various aircraft sensors and, using a variety of electronic databases, generating intuitive symbols that aid the pilot.
The moving map of the present invention displays about an aircraft symbol a computed intersection of the aircraft""s glide and the terrain. The intersection computation may take into consideration external factors such as wind and terrain elevations. The computation further takes into consideration aircraft specific factors such as glide ratio, configuration, weight, center of gravity, altitude, airspeed, and heading. The safe glide area may be shown by a boundary line, shaded area or other means. Likewise, the safe glide area may be converted to perspective view and shown on the primary flight display. It is also an object of the present invention to display optimal glide speed. Factors that may be included in the optimal glide speed computation include wind, weight, center of gravity, configuration, and altitude.
Other objects, advantages and novel features of the present invention will become apparent from the following detailed description of the invention, when considered in conjunction with the accompanying drawings.